Many motor-operated appliances, in particular centrifugal pumps, have the capability to operate when supplied by any of several different power supplies when the appropriate electrical connection modifications are made. It is well known in the industry how to produce motors that drive pumps that are of dual-voltage design. Conversion from one voltage to the other only requires reconnection of the motor leads. This reconnection of the leads occurs in the factory at the time the power cord is attached to the pump or may be determined in the field. Additionally, at these times, the length of the power cord is another option that may be determined.
To accommodate the possible wide range of voltage connection and cord length combinations demanded in customer applications, many different pump and power cord configurations are required to be kept in inventory. This consequently and undesirably increases cost and complicates distribution requirements. What is needed is a means to delay the determination of cord length and selection of voltage rating connections until a pump system is ready to be installed in the field and precise requirements are known by the customer as well as an easy means to implement such desired configurations.
As a matter of convenience, this specification will refer to “115 volt” single phase power and “230 volt” single-phase power. In reality, and as will be readily understood, the actual voltages may vary. Furthermore, different countries may provide standard electrical power at different voltages and frequencies than 115 volts or 230 volts. For that reason, the term “115 volt” refers to a first or lower nominal alternating current voltage level that is commercially available and the term “230 volt” refers to a second or higher nominal alternating current voltage level. In many countries, for example, the United States of America, the second or higher nominal voltage level is approximately double that of the first. Furthermore, although certain portions of the specification may refer to single phase power, it should be understood that the application may be used with three phase power as well.